HVAC Serial Number Age Decoder
Decode common US HVAC, water heater, and boiler serial date codes to estimate manufacture date and age. Built for inspectors as a quick educational reference—not a substitute for reading the rating plate or assessing equipment condition.
Decode result
Enter a brand and serial number to decode manufacture date, age, and a copy-ready narrative.
Methodology
Enter brand, serial number, and equipment type. Optional refrigerant type and known install year narrow ambiguous letter-cycle candidates when more than one manufacture year is possible. The decoder applies brand-family date-code rules (week/year, month/year, letter cycles, and manufacturer lookup tables) and returns a manufacture date estimate, approximate age, and a typical service-life band.
Brand coverage
Shipped families cover the major US residential nameplates and their rebadges, including Carrier / Bryant / Payne; Goodman / Amana (Houston unitary); Trane / American Standard; Lennox / Armstrong / Allied; York / Coleman / Luxaire / JCI UPG; Rheem / Ruud / Richmond; ICP (Heil, Tempstar, Comfortmaker, and related); Nortek / Nordyne badge lines; A.O. Smith / State water heaters; Bradford White; Bosch / Buderus (2010+ three-digit table); Weil-McLain CP ranges; and GE Zoneline PTACs. Some ductless brands are recognized as non-decodable from the serial alone and point you to the printed MFG date instead.
Older or rare eras without corroborated fixtures are excluded on purpose. Manufacture date is not install date—equipment can sit in inventory or be relocated years later.
Educational estimate only—not a condition assessment, defect finding, failure prediction, or warranty determination. A decoded build (manufacture) date is not the same as the install date. Always verify against the rating plate and evaluate equipment condition separately.